In a support structure for attaching a long article such as a fuel pipe, brake oil pipe or wire harness of an automobile, it is desired to prevent vibration from being transmitted from the pipe or the like to an automobile body or the like or from the automobile body or the like to the pipe or the like. Heretofore, for the purpose of such vibration insulation, there has been typically employed a technique of attaching the pipe or the like to a fastener with winding a rubber vibration insulator around the pipe or the like. One such example includes a fastener for a pipe or the like described in Japanese Patent Laid-Open No. 9-250517. In this fastener, a vibration insulation characteristic is achieved by combining a flexible plastic material with a rigid plastic material. This technique is essentially required to use two kinds of plastic materials, resulting in increased cost and weight. Japanese Patent Laid-Open No. 7-310866 discloses a pipe fastener in which a flexible bridge member is provided between a stud engagement portion and a pipe holding portion to prevent vibration transmission between the stud engagement portion and the pipe holding portion. Japanese Patent Laid-Open No. 61-116189 also discloses a pipe fastener in which a flexible strip is provided between a stud engagement portion and pipe holding portion to prevent vibration transmission between the stud engagement portion and the pipe holding portion. These fasteners can be formed of a single plastic material, and thereby the problem of cost overrun would be solved. However, somewhat specified configuration of these fasteners can cause a problem of poor versatility, because their holding force is not sufficient to hold three or more of pipes or their molding process is complicated.
Japanese Patent Laid-Open Nos. 7-91570 and 9-126357 disclose a fastener for a pipe or the like, which includes a base portion, a pipe holding portion connected integrally with the base portion, and a stud engagement portion provided at the base portion and adapted to engage with a stud standing on a workpiece such as an automobile body, wherein engaging the stud engagement portion with the stud allows an elongated article such as a pipe held in the pipe holding portion to be mounted on the workpiece. This fastener is intended to reduce the number and total sectional area of connection portions between the stud engagement portion and the pipe holding portion to prevent vibration transmission between the stud engagement portion and the pipe holding portion.
The fastener in Japanese Patent Laid-Open Nos. 7-91570 and 9-126357 would provide a certain advantageous result in terms of preventing the vibration transmission between the stud engagement portion and the pipe holding portion. Further, the fastener could be formed in a suitable configuration for holding three or more of pipes. However, there is a problem of slightly low strength in the connection portions between the stud engagement portion and the pipe holding portion, because it is too enhanced to prevent the vibration transmission between the stud engagement portion and the pipe holding portion.
Therefore, in a fastener for a pipe or the like, having a stud engagement portion through which an elongated article such as a pipe held by the fastener is mounted on a workpiece such as an automobile body, it is an object of the present invention to enable the fastener to maintain high connection strength between the stud engagement portion and a pipe holding portion of the fastener while keeping a sufficient isolating property for vibration transmitted from the pipe or the like to the car body (or vise versa).